65 results about "Dextran sulfate" patented technology

The invention discloses a method for detecting the residual quantity of dextran sulfate sodium in an antibody. Specifically, the invention provides a method for detecting the residual quantity of dextran sulfate sodium in an antibody, which comprises the following steps: removing protein in the antibody, and reacting with a 2-aminopyridine solution; a high performance liquid chromatography method is adopted to detect a test sample and sodium dextran sulfate standard substances with different concentrations. The detection method disclosed by the invention is low in detection limit, high in accuracy and suitable for analyzing the residual quantity of dextran sulfate in the antibody.

The invention discloses a plant lactobacillus JNL0074 strain, application thereof and a microbial agent, and belongs to the technical field of microorganisms. The lactobacillus plantarum JNL0074 is preserved in the China General Microbiological Culture Collection Center on June 24, 2024, the preservation address is No.3, No.1 yard, Beichen West Road, Chaoyang District, Beijing, the preservation number is CGMCC NO: 31047, and the lactobacillus plantarum is classified and named as lactobacillus plantarum. The strain can realize high yield of indole-3-lactic acid in an MRS culture medium. An in-vitro experiment result shows that supernate of the strain remarkably inhibits inflammatory polarization of macrophages stimulated by lipopolysaccharide and secretion of inflammatory factors. Animal experiment results show that the strain can significantly inhibit sodium dextran sulfate induced colonic tissue inflammatory factor secretion and intestinal barrier injury, alleviate ulcerative colitis, and show a huge application value.

The invention discloses a strain of lactobacillus pentosus JNL0030, application thereof and a microbial preparation, and belongs to the technical field of microorganisms. The lactobacillus pentosus JNL0030 is preserved in the China General Microbiological Culture Collection Center on June 24, 2024, the preservation address is No.3, No.1 yard, Beichen West Road, Chaoyang District, Beijing, the preservation number is CGMCC (China General Microbiological Culture Collection Center) NO: 31045, and the lactobacillus pentosus is classified and named as lactobacillus pentosus. The strain can realize high yield of indole-3-lactic acid in an MRS culture medium. An in-vitro experiment result shows that supernate of the strain remarkably inhibits inflammatory polarization of macrophages stimulated by lipopolysaccharide and secretion of inflammatory factors. Animal experiment results show that the strain can significantly inhibit sodium dextran sulfate induced colonic tissue inflammatory factor secretion and intestinal barrier injury, alleviate ulcerative colitis, and show a huge application value.

The invention discloses lactobacillus delbrueckii JNL0010, application of the lactobacillus delbrueckii JNL0010 and a microbial agent, and belongs to the technical field of microorganisms. The lactobacillus delbrueckii JNL0010 is preserved in the China General Microbiological Culture Collection Center on June 24, 2024, the preservation address is No.3, No.1 yard, Beichen West Road, Chaoyang District, Beijing, the preservation number is CGMCC NO: 31042, and the lactobacillus delbrueckii JNL0010 is classified and named as lactobacillus delbrueckii subsp.bulgaricus. The lactobacillus delbrueckii JNL0010 is named as lactobacillus delbrueckii subsp.bulgaricus. The strain can realize high yield of indole-3-lactic acid in an MRS culture medium. An in-vitro experiment result shows that supernate of the strain remarkably inhibits inflammatory polarization of macrophages stimulated by lipopolysaccharide and secretion of inflammatory factors. Animal experiment results show that the strain can significantly inhibit sodium dextran sulfate induced colonic tissue inflammatory factor secretion and intestinal barrier injury, alleviate ulcerative colitis, and show a huge application value.

The invention discloses lactobacillus reuteri with antioxidant, anti-inflammatory and anti-hypoxia capabilities, the name of the lactobacillus reuteri is QM11, the classification name of the lactobacillus reuteri is CGMCC NO.31541, the preservation number of the lactobacillus reuteri is CGMCC NO.31541, the preservation date of the lactobacillus reuteri is No.3, Yard 1, Beichen West Road, Chaoyang District, Beijing on August 5, 2024, and the preservation number of the lactobacillus reuteri is CGMCC NO.31541, the preservation number of the lactobacillus reuteri is CGMCC NO.31541, the preservation number of the lactobacillus reuteri is CGMCC NO.31541, and the preservation number of the lactobacillus reuteri is CGMCC NO.31541. The preservation unit is China General Microbiological Culture Collection Center (CGMCC). The lactobacillus reuteri is separated from faeces of healthy yaks in Qinghai province, has relatively strong acid and cholate tolerance, has relatively good antioxidant and anti-inflammatory capacities, and has a relatively strong inhibition effect on pathogenic bacteria such as yak-derived pathogenic escherichia coli, staphylococcus aureus and salmonella typhimurium; the sodium dextran sulfate induced mouse colitis symptom is relieved, and the hypoxia tolerance of the mouse is improved. The lactobacillus reuteri disclosed by the invention can be used for preparing medicines or microecological preparations for resisting oxidation, inflammation and hypoxia, and has a very wide application prospect.

The invention discloses a preserving fluid for stably preserving sample DNA at normal temperature and a preparation method thereof, and belongs to the technical field of biological sample preservation. The preserving fluid comprises a lysis system, a nucleic acid protection system and a buffering and stabilizing system, the cracking system comprises a composite surfactant and an enzymolysis auxiliary agent; the composite surface active agent is prepared from polyether polyol fatty acid ester and cocamidopropyl hydroxy sulfobetaine; the enzymolysis auxiliary agent comprises lysozyme Lyso-V and protease K; the nucleic acid protection system comprises a nitrogen heterocyclic polyamine-carboxylic acid derivative and dextran sulfate; the nitrogen heterocyclic polyamine-carboxylic acid derivative comprises 1, 4, 7, 10-tetraazacyclododecane-N, N ', N' ', N ''tetraacetic acid, 1, 4, 7-triazacyclononane-N, N', N''-triacetic acid, disodium ethylene diamine tetraacetate-nitrogen heterocyclic derivative, and diethylenetriamine pentaacetic acid-piperazine derivative, and the nitrogen heterocyclic polyamine-carboxylic acid derivative comprises 1, 4, 7, 10-tetraazacyclododecane-N, N ', N '', N'' tetraacetic acid, 1, 4, 7-triazacyclononane-N, N', N ''-triacetic acid. The buffering and stabilizing system comprises an amphoteric buffering agent and a polymer stabilizer; the amphoteric buffering agent comprises 2-(N-morpholino) ethanesulfonic acid and N-tri (hydroxymethyl) methylglycine.

The invention belongs to the technical field of biological medicines, and particularly relates to application of extracellular vesicle-like particles derived from divaricate saposhnikovia roots in preparation of medicines for preventing and treating intestinal diseases. Research on the physiological efficacy of the extracellular vesicle-like particles from divaricate saposhnikovia root shows that the extracellular vesicle-like particles can relieve colon shortening and colon tissue damage caused by dextran sodium sulfate, relieve intestinal inflammation and promote repair of intestinal barriers including mechanical barriers, chemical barriers and immune barriers. The polypeptide has potential for preparing the medicine for treating the intestinal diseases, and a new strategy is provided for preventing or treating the intestinal diseases.

The present invention discloses a polythiophene-based photothermal fabric based on dextran sulfate as a template and a preparation method and application thereof, belonging to the technical field of functional textile processing. The preparation method of the present invention specifically comprises the following steps: (1) grafting dextran sulfate onto the fiber surface; (2) in-situ polymerization of polythiophene onto the fiber surface; (3) fabric washing and drying post-treatment; the present invention aims to form a template for inducing polymerization of thiophene monomers by grafting dextran sulfate onto the fiber surface; and then using an initiator to catalyze in-situ polymerization of 3,4-ethylenedioxythiophene monomers on the fiber surface to prepare polythiophene-based photothermal fabrics; after washing and drying, a fabric with a durable and stable photothermal effect is obtained. Compared with the traditional method of applying PEDOT:PSS to the fabric surface by an impregnation method or a coating method for preparing a photothermal fabric, the method of the present invention has the advantages of good photothermal uniformity, high efficiency, durable photothermal effect and strong photothermal bactericidal property.

The invention relates to the technical field of pharmaceutical preparations, in particular to a florfenicol preparation with high water solubility and antibacterial effect and a preparation method of the florfenicol preparation. The florfenicol preparation with high water solubility and antibacterial effect is prepared from the following raw materials in parts by mass: 20 to 30 parts of florfenicol, 30 to 50 parts of beta-cyclodextrin, 30 to 50 parts of solid polyethylene glycol, 2 to 5 parts of lauryl sodium sulfate, 100 to 200 parts of dopamine aqueous solution and 1 to 5 parts of dextran sulfate aqueous solution. Wherein the concentration of the dopamine aqueous solution is 1-3 g / L, and the concentration of the dextran sulfate aqueous solution is 0.1-0.5 mol / L. The preparation method is relatively wide in application, is commonly used for granulating heat-sensitive materials and medicines which are easy to decompose when encountering water, and is convenient for subsequent re-tabletting or encapsulation; and compared with wet granulation, the method has the advantages of simple process, low energy consumption, low filler consumption and the like.

This invention relates to an absorbable, slow-release regulator for off-season antler growth in sika deer and red deer, and its preparation method, belonging to the field of off-season antler growth regulators. The regulator comprises 330 mg–360 mg medroxyprogesterone acetate (MPA), 50 mg–55 mg dextran sulfate (DS), and 200 mg–220 mg sodium hyaluronate (HA), diluted with water for injection to a final volume of 1.0 mL. The molecular weight of medroxyprogesterone acetate (MPA) is 386.52 kDa; the molecular weight of dextran sulfate (DS) is 36–50 kDa; and the molecular weight of sodium hyaluronate (HA) is 20–400 kDa. This invention utilizes exogenous progesterone to induce off-season antler growth in male deer through hormonal regulation. The use of absorbable materials is environmentally friendly and harmless to the body, allowing for natural absorption and normal excretion through the body's metabolic processes. A single injection is sufficient to provide efficacy for over 35 days. Using progesterone to regulate off-season antler growth is low-cost and has a high success rate.

This invention belongs to the field of vertebrate technology, specifically relating to a method for constructing a complex inflammatory animal model in middle-aged and elderly individuals and its related applications. The method includes: selecting adult animals for adaptive feeding, daily subcutaneous injection of D-galactose to establish a susceptibility to aging and oxidative stress, and administering sodium dextran sulfate (DSS) solution within a specific time window to induce intestinal inflammation, forming a complex inflammatory state through gut-hepatic axis interactions. The constructed animal model simultaneously exhibits intestinal inflammatory damage, abnormal hepatic oxidative stress, and aging-related characteristics, realistically simulating the pathological process of gut-hepatic axis dysfunction in middle-aged and elderly individuals. This model is suitable for screening and evaluating drugs, medical nutrition products, and functional foods that improve gut-hepatic axis dysfunction, providing a reliable technical platform for research on related disease mechanisms and the development of interventional substances.

The present invention provides a composition for external use that enhances the effect of heparinoids, which are expensive and have limitations on the amount that can be used. [Solution] A composition for external use containing 0.01 to 0.3 mass % of a heparinoid and 0.1 to 2 mass % of dextran sulfate sodium.

To provide a drug having positive effects in subjects suffering from neurological diseases, including neurodegenerative diseases, demyelinating diseases, neuro ischemic diseases and neuromuscular diseases.SOLUTION: Dextran sulfate, or a pharmaceutically acceptable derivative thereof, is used to induce differentiation of glial cells and neurons.SELECTED DRAWING: Figure 12

The invention discloses a drug delivery system containing loaded adriamycin as well as a preparation method and application of the drug delivery system. The drug delivery system comprises poly (beta-amino ester) coupled with adriamycin, wherein the surface of the poly (beta-amino ester) is coated with dextran sulfate, and the poly (beta-amino ester) takes a fourth-generation lysine dendritic molecule Lys-G4 as a core. The drug delivery system has a pH-dependent drug release characteristic, has remarkable toxicity to C6 and U87MG glioma cells, has the capabilities of inducing apoptosis, inhibiting migration and targeting subcellular localization, and can effectively penetrate through a blood-brain barrier model and 3D tumor spheres. The delivery system is compounded with PLA-PEG-PLA thermosensitive hydrogel, and the thermosensitive hydrogel with a drug storage function is successfully constructed. Good tumor inhibition effect and biocompatibility are shown in nude mouse subcutaneous and in-situ glioma models. The invention not only provides a new strategy for overcoming the blood brain barrier, but also can effectively reduce the systemic toxicity, and opens up a new research thought and method for glioma treatment.

The present invention discloses a method for constructing an animal model of ankylosing spondylitis and chronic enteritis. By using proteoglycan PG immune induction and sodium dextran sulfate chemical induction methods, an animal model is established that simulates the coexistence of ankylosing spondylitis and chronic enteritis in terms of symptoms, imaging changes, and pathological characteristics. The model mice exhibit imaging changes similar to those of human ankylosing spondylitis, such as sacroiliac joint bone erosion and sclerosis, narrowing and roughening of the joint space, and worm-eaten changes. Furthermore, they exhibit pathological changes similar to those of human chronic enteritis, such as intestinal epithelial cell destruction, glandular disorder, crypt structure destruction, goblet cell reduction, and inflammatory cell infiltration. This model can be used to study the interaction mechanism between the two diseases, explore new therapeutic targets, and help evaluate the potential application of new drugs in the treatment of ankylosing spondylitis and chronic enteritis, providing an important tool for mechanism research and drug development of such co-morbidities.

The invention belongs to the technical field of biology, and particularly relates to a bacteriostatic agent and a preparation method and application thereof. Comprising the following steps that antibacterial peptide modified silver nanoparticles are prepared, specifically, antibacterial peptide and silver nitrate grow in situ under the action of a reducing agent, and the antibacterial peptide modified silver nanoparticles are obtained; preparing a bacteriostatic agent: dissolving the antibacterial peptide modified silver nanoparticles by using a cross-linked substance of chitosan and dextran sulfate to obtain the bacteriostatic agent; the charge of the cross-linked substance of the chitosan and the dextran sulfate is 0. Through mutual attraction of positive charges of the antibacterial peptide and negative charges of the silver nanoparticles, the silver nanoparticles wrapped by the antibacterial peptide are formed, the self-assembly or irregular agglomeration behavior of the antibacterial peptide is effectively controlled, a nanometer network formed by crosslinking chitosan with dextran sulfate can stabilize the nanometer form of the silver nanoparticles, and the antibacterial activity of the antibacterial peptide is improved. The core-shell structure formed by the silver nanoparticles wrapped by the antibacterial peptide can be stabilized, the silver nanoparticles wrapped by the antibacterial peptide can also be dispersed, and mutual agglomeration of the core-shell structure is prevented.

This invention provides a soil conditioner prepared from Phyllanthus emblica pomace and its preparation method, relating to the field of plant by-product processing technology. The soil conditioner comprises Phyllanthus emblica pomace, animal manure, biochar, modified starch, modified pectin, sodium dextran sulfate, a compound microbial agent, and Sphingomonas sphingosine monocytogenes. The Phyllanthus emblica pomace is first soaked in sodium chloride solution, then fermented and filtered with Sphingomonas sphingosine monocytogenes. The filtered residue is then sterilized, mixed with animal manure, and composted. The filtrate is mixed with other substances and then combined with the composted fertilizer. This invention overcomes the shortcomings of existing technologies, effectively regulates alkaline soil, and to a certain extent, can remediate heavy metals in the soil and promote crop growth.

The invention discloses a sweet potato pinniform mottle virus RT-LAMP (Reverse Transcription Loop-Mediated Isothermal Amplification) visual detection kit. Comprising LAMP primers, freeze-dried microspheres and water. The freeze-dried microspheres are prepared from the following components: HotStart Bst4. 2DNA / RNA (Ribonucleic Acid) polymerase, Helicaser, dNTP (Deoxyribose Nucleic Acid), Mg < 2 + >, a reaction buffer, an L-HNB color change indicator Leuco-HNB, a leuco HNB dye and a stabilizer. The RT-LAMP visual rapid detection method provided by the invention is high in sensitivity and good in specificity, and is suitable for rapid field detection of SPFMV. Dextran sulfate and polyethylene glycol 8000 are used as compound stabilizers in the freeze-dried microspheres, so that the detection sensitivity is improved.

This invention discloses a preservation solution for preserving sample DNA at room temperature and its preparation method, belonging to the field of biological sample preservation technology. The preservation solution comprises: a lysis system, a nucleic acid protection system, and a buffering and stabilizing system; the lysis system comprises a complex surfactant and an enzymatic hydrolysis aid; the complex surfactant comprises: polyether polyol fatty acid ester and cocamidopropyl hydroxysulfonate betaine; the enzymatic hydrolysis aid comprises lysozyme Lyso-V and proteinase K; the nucleic acid protection system comprises: nitrogen-heterocyclic polyamine-carboxylic acid derivatives and dextran sulfate; the nitrogen-heterocyclic polyamine-carboxylic acid derivatives comprise: 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''tetraacetic acid, 1,4,7-triazacyclononane-N,N',N''-triacetic acid, disodium ethylenediaminetetraacetate-nitrocyclic derivative, and diethylenetriaminepentaacetic acid-piperazine derivative; the buffering and stabilizing system comprises: an amphoteric buffer and a polymeric stabilizer; the amphoteric buffer comprises: 2-(N-morpholino)ethanesulfonic acid and N-tris(hydroxymethyl)methylglycine.

The application relates to the technical field of pharmaceutical preparations, in particular to a florfenicol preparation with high water solubility and bacteriostatic effect and a preparation method thereof.The raw materials of the florfenicol preparation with high water solubility and bacteriostatic effect include, by mass fraction, florfenicol 20-30 parts, beta-cyclodextrin 30-50 parts, solid polyethylene glycol 30-50 parts, sodium dodecyl sulfate 2-5 parts, dopamine aqueous solution 100-200 parts and dextran sulfate aqueous solution 1-5 parts; wherein the concentration of the dopamine aqueous solution is 1-3 g / L, and the concentration of the dextran sulfate aqueous solution is 0.1-0.5 mol / L.The application has a wide application range, is commonly used for granulation of heat-sensitive materials and drugs which are easily decomposed in water, and is convenient for subsequent re-compression tabletting or encapsulation; and compared with a wet granulation method, the application has the advantages of simple process, low energy consumption, small filler consumption and the like.

Ferrous fumarate, gellan gum and dextran sulfate are prepared into an ion-sensitive tablet, and the surface of the ion-sensitive tablet is subjected to enteric coating, so that the ion-sensitive tablet basically does not release iron elements in the stomach, and the ion-sensitive tablet is quickly converted into iron-containing gel when entering the intestinal tract, so that the iron-containing gel can be quickly dissolved in the intestinal tract. Further, slow and uniform release in intestinal tracts is realized, and stimulation of high-dose iron to gastrointestinal tracts is reduced; in addition, ferrous fumarate and Chinese herbal medicines are combined to form beneficial complementation, so that the dual purposes of supplementing iron and tonifying qi and blood are achieved, and the iron-deficiency anemia is effectively improved.

This invention, entitled "A Composition Containing Pentadecanoic Acid, Parabacterium Species Outer Membrane Vesicles Containing the Composition, and Their Applications," belongs to the field of probiotics and microbial preparations technology. The technical problem this invention aims to solve is that beneficial live bacteria have weak colonization ability in the gut, are easily affected by the gastrointestinal environment, exhibit unstable individual responses, and struggle to simultaneously address immune regulation and barrier repair. This invention provides a composition containing pentadecanoic acid, Parabacterium Species-derived outer membrane vesicles, and their applications. The outer membrane vesicles are derived from *Parabacterium difficile* and are rich in pentadecanoic acid, palmitic acid, and octadecanoic acid. The composition and outer membrane vesicles prepared by this invention can significantly inhibit macrophage M1 polarization and reduce pro-inflammatory cytokines. TNF-α , IL-6 and IL-1 β It can lower the expression level of [something], reduce intracellular reactive oxygen species levels, improve mitochondrial function, significantly alleviate symptoms of colitis induced by sodium dextran sulfate, regulate the intestinal flora structure, and increase the abundance of beneficial bacteria.

The invention provides application of barley pest larva defatted protein powder in preparation of drugs for treating inflammatory bowel diseases. The invention belongs to the technical field of medicine, and by establishing a dextran sodium sulfate induced mouse IBD model and lavaging barley pest larva defatted protein powder, it is found that the traditional Chinese medicine composition can relieve IBD mouse colitis symptoms, restore colon length, relieve mucosal lesion, retain goblet cell and crypt structures, reduce inflammatory cell infiltration and down-regulate inflammatory cytokine expression; the compound is expected to play an important role in preparing medicines for treating inflammatory enteritis.

The invention discloses a high-density lipoprotein cholesterol determination kit and a detection method thereof. The kit comprises a reagent 1 and a reagent 2, the reagent 1 is prepared from a buffer solution, inorganic salt, dextran sulfate, a macromolecular cationic polymer, TOOS, peroxidase, ascorbic acid oxidase and a preservative; the reagent 2 is prepared from a buffer solution, a surfactant 1, 4-aminoantipyrine, cholesterol oxidase, cholesterol esterase and a preservative. The kit has the advantages of being high in accuracy, good in anti-interference performance and the like, automatic detection can be achieved on a full-automatic biochemical analyzer, and compared with a traditional dextran sulfate precipitation method, the content of high-density lipoprotein cholesterol (HDL-C) in a lipid turbid sample can be more accurately detected.

The invention provides a preparation method of sodium dextran sulfate and application of the sodium dextran sulfate in red fading cosmetics, and relates to the technical field of catalytic synthesis. The preparation method comprises the following steps: S1, mixing glucan with the molecular weight of 1.5-30 thousand, beta-glucanase and a ZSM-5 molecular sieve to obtain pretreated glucan; s2, the pretreated dextran, a sulfonating reagent and a catalyst are mixed for a reaction, and dextran sulfate is obtained; s3, enabling the dextran sulfate to react with sodium salt, so as to obtain the dextran sulfate sodium. According to the specific preparation method disclosed by the invention, high-purity dextran sodium sulfate with specific molecular weight is obtained through specific raw materials, reaction conditions, refining steps, refining solvents and the like, and the stability is improved.

The invention relates to a preservation method and a preservation solution of exosomes, and belongs to the technical field of biology, the preservation solution comprises trehalose, cane sugar, sodium hyaluronate, polyethylene glycol, dextran sulfate, an HEPES buffer solution and mannitol, the preservation method comprises the following steps: mixing purified exosomes with the exosome protection solution to obtain a mixture, and adding the mixture into the exosome protection solution to obtain the exosome preservation solution. Sub-packaging the mixture, and directly cryopreserving the sub-packaged sample at the temperature of-80 DEG C or lower; in a word, through a rigid network formed by the sodium hyaluronate and the polyethylene glycol, the aggregation and fusion of the exosome in the freezing and thawing process are effectively inhibited. The embodiment shows that after three times of freeze-thaw cycles, the particle size change rate of the exosome is less than 6%, and the particle recovery rate is close to 90%.

The invention discloses a tissue sealing reagent, a multi-index RNA-protein co-dyeing method and application, and belongs to the technical field of molecular biology. The tissue sealing reagent comprises the following components: ethylene carbonate, dextran sulfate, sodium chloride, citric acid, trisodium citrate dihydrate and herring sperm DNA (deoxyribonucleic acid). The invention further discloses a multi-index RNA-protein co-dyeing method, multi-index co-dyeing of RNA-protein on the same tissue slice can be achieved, multiple RNA in-situ hybridization strategies are compatible, and an effective solution is provided for the non-specific dyeing problem occurring in the existing hybridization strategies. By optimizing sample treatment, a co-staining method and a signal enhancement strategy, high-resolution spatial localization of gene expression on the tissue slice is achieved, the method is particularly suitable for research of cell distribution and gene expression modes of complex tissues, and important technical support can be provided for research of disease mechanisms, development of targeted therapy and precision medicine.

The present application relates to the technical field of veterinary medicine, and discloses a kind of absorbable sustained-release agent for inhibiting the fighting behavior of male deer during estrus, comprising the following steps: stirring micronized medroxyprogesterone acetate with dextran sulfate and water for injection to obtain a homogeneous suspension paste; adding sodium hyaluronate dry powder without adding solvent to knead, and through competitive water absorption, dextran sulfate is dehydrated to form a physical coating layer on the surface of drug particles, obtaining a non-saturated hard rubber mass; after cooling, the remaining water for injection is pre-cooled and forced to pass through a microporous screen to achieve reciprocating convection extrusion, and then the product is obtained by swelling after standing.The present application utilizes the double retardation effect of interface physical coating layer and three-dimensional network of gel to inhibit the initial drug burst of long-acting preparation, prevent the gravity settlement of drug particles, achieve the long-term stable release of medroxyprogesterone acetate in animal body, and further reduce the fighting behavior of male deer during estrus.

This invention provides the application of *Pleurotus oosporum* polysaccharide in the preparation of drugs and health foods that regulate intestinal barrier function or protect against intestinal damage-related diseases. Its protective effect against a mouse model of intestinal damage induced by sodium dextran sulfate was investigated. Results showed that *Pleurotus oosporum* polysaccharide significantly improved symptoms such as weight loss, loose stools, and colonic atrophy caused by intestinal damage in mice, reduced the disease activity index, inhibited colonic epithelial destruction, inflammatory cell infiltration, and goblet cell necrosis, and enhanced intestinal mucosal barrier function. As a fungus, *Pleurotus oosporum* has high safety and is a potential source of active ingredients against intestinal damage, showing promising development prospects in intestinal barrier protection.

The invention relates to the technical field of biological medicine, and provides a preparation method and application of a macrophage targeting exosome. The method comprises the following steps: firstly, stimulating stem cells by utilizing N-azide acetyl mannosamine-tetra-acylation (Ac4ManNAz); then, dibenzocyclooctyne-dextran sulfate (DBCO-DS) is adopted to stimulate the pretreated stem cells, and the stem cells are modified; after the stem cells are cultured, the stem cell exosome of the targeted macrophage is obtained through a gradient centrifugation method and an ultra-high-speed centrifugation method. Through verification, the exosome can effectively regulate and control the polarization phenotype of the macrophage to be converted from M1 to M2.